Nitrogen transfer and humus dynamics as the key to climate protection

Field day of the HumusClimateNet at Hof Buchwald

On August 20, 2024, the HumusClimateNet field day attracted numerous interested parties to the idyllically situated Naturland farm Hof Buchwald in Nidderau. Under the theme of “Intercropping: nitrogen transfer and humus dynamics”, the day was all about innovative cultivation techniques that not only improve soil fertility but also contribute to climate protection.

Hof Buchwald: A model farm for sustainable agriculture

It is not without reason that Hof Buchwald is part of the HumusKlimaNetz and is one of the 50 pilot farms for water-conserving agriculture in the Main-Kinzig district. The farm relies on measures that not only help to preserve the soil, but also contribute to reducing CO2 emissions.

Hof Buchwald is an organic farm with 100 hectares of arable land and 10 hectares of grassland. The land is used to grow fodder crops such as clover grass, silage maize, legumes and cereals. The focus on soil protection and soil fertility is particularly impressive. The farm minimizes erosion and strengthens the soil structure with methods such as intensive intercropping, direct sowing of row crops such as maize and soybeans as well as slope-parallel cultivation.

The HumusClimateNet: Climate protection through soil health

The HumusClimateNet is a nationwide model project that is testing innovative methods for improving humus build-up with 150 farms, both organic and conventional. The aim is to make agricultural practice more climate- and soil-friendly. This includes measures such as extended crop rotations, the cultivation of catch crops and agroforestry systems in which trees and arable land are combined. Scientific monitoring ensures the evaluation of the results and helps to classify the contribution of the measures to climate protection.

Focus on intercropping

After the welcoming address by the farm managers Philipp Stelz and Rainer Vogel and the presentation of the HumusClimateNetwork by Romina Mejow, technical presentations were on the agenda. Christopher Brock from Forschungsring e.V. and Johanna Hoppe from the University of Kassel/PFN presented the effects of intercropping in organic farming in an exciting keynote speech. “Ploughing, heaping, cultivating – what happens after ploughing?” was the title of the presentation, which immersed the participants
in the complex dynamics of nitrogen transfer and humus formation.

One highlight was the soil talk in alfalfa clover grass, where the humus and climate protection performance of alfalfa was discussed in detail. With the soil profile excavated, the participants were able to examine the soil structure and the course of the alfalfa roots directly on site. Moritz Böhm, farm supervisor in the HumusKlimaNetz, Bioland Beratung GmbH, described the biopores, which are formed by alfalfa roots growing up to 130 cm deep, as “highways” in the soil that connect the topsoil and subsoil with each other.

Initial results from the UMKREIS project

A particular focus of the field day was on the initial results from the PFN project UMKREISproject, which were presented by Johanna Hoppe. Her research showed that winter ploughing with a plough or ridger is advantageous for most locations – the ridger in particular proved to be a more soil-friendly method. On deeper soils, non-rotational spring plowing led to yield losses due to increased weed pressure and lower nitrogen levels. For sandier soils, however, a winter-hardy catch crop with spring ploughing could be the better choice, as lower yield differences were observed here.
Climate protection advice in an agricultural context

In addition to the technical aspects of intercropping, the role of climate protection advice was also discussed. In a presentation by Lisa Fröhlich and Robert von Klitzing from Landesbetrieb Landwirtschaft Hessen (LLH), the participants learned how farms can maximize their contribution to climate protection through targeted advice.

Conclusion

The field day at Hof Buchwald not only offered in-depth insights into the practical implementation of sustainable cultivation strategies, but also highlighted the central role of agriculture in the fight against climate change. The combination of scientific presentations, practical demonstrations and lively discussions left a lasting impression on the participants
. Hof Buchwald impressively demonstrates how modern agriculture can not only protect the soil, but also the climate – an inspiring day for everyone involved.